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प्रश्न
When the positive charge on an ion increases or the negative charge on them decreases it is called as _______.
विकल्प
reduction
corrosion
oxidation
decomposition
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उत्तर
When the positive charge on an ion increases or the negative charge on them decreases it is called as oxidation.
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संबंधित प्रश्न
Corrosion can be prevented by using ……………. solution.
What is meant by rust?
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\[\ce{SO2 + 2H2S -> 2H2O + 3S}\]
In this reaction, which substance is oxidised and which one is reduced?
The addition of hydrogen to a substance is called ______ whereas removal of hydrogen is called ______.
Give an example of an oxidation reaction.
Is oxidation an exothermic or an endothermic reaction?
Explain the following in terms of gain or loss of oxygen with one example:
Reduction
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Oxidation is the removal of ......................and addition of ....................
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In redox reaction oxidation and reduction occur ............................
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Fe + S → FeS
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2Mg + O2 → 2MgO
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burning
State whether the following conversion is oxidation or reduction:
PbO2 + SO2→ PbSO4
State whether the following conversion is oxidation or reduction:
K → K+ + e-
Name:
a substance that will reduce aqueous Iron(III)ions to iron(II)ions.
State a reason why, when hydrogen is passed over heated copper oxide, the resultant product formed, differs in colour from the original reactant.
Give two tests for a reducing agent.
Oxidising agents are also called as ______ because they remove electrons form other substances.
Rusting of iron involves a chemical reaction which is a combination of:
The process of reduction involves ____________.
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Identify the oxidising agent (oxidant) in the following reactions
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Which among the following are physical or chemical change?
Sublimation of solid ammonium chloride
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
Silver metal does not show any change
Explain this observation giving suitable reason.
During the reaction of some metals with dilute hydrochloric acid, following observations are made.
Some bubbles of a gas are seen when lead (Pb) is reacted with the acid.
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Identify the following reactions as oxidation/reduction/redox reaction
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What are reducing agents? Give examples.
What are redox reactions? Give examples.
What is rancidity?
Find the oxidation number of the element in the following compound.
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Answer the questions that follow based on this reaction.
- Write the equation.
- What type of reaction is it?
- Complete the blanks:
In this reaction, an oxygen atom goes away from CuO (copper oxide), which means that ______ of copper oxide takes place, whereas a hydrogen molecule takes up an oxygen atom and water (H2O) is formed, meaning ______ of hydrogen takes place.
A reddish brown metal used in electrical wires when powdered and heated strongly turns black. When hydrogen gas is passed over this black substance, it regains its original colour. Based on this information answer the following questions:
- Name the metal and the black substance formed.
- Write balanced chemical equations for the two reactions involved in the above information
